I went to my old server and revisited my old Docker setup (detailed in a previous post here) and it was in a bit of a state.
It was using a very old version of Docker and it was a pain to get a new certificate etc.

Anyway, I decided to rework the whole shebang:

updated Docker (v1.12 - latest at the time) so I can use Docker Compose (v1.8.0), allowing the setup to be a bit more flexible in the long run.

SSH into the box and update the SSH config file (sshd_config) to stop SSH connections using the password.
(You might want to setup an SSH config to make this easier: info)

sudo nano /etc/ssh/sshd_config

Change or add the following line to the ‘Authentication’ section:

PermitRootLogin without-password

Restart the SSH server for the changes to take effect

ps auxw | grep ssh
kill -HUP <PID of SSH process>

Setup swap space for MariaDB use later on

The database eats up a lot of memory and I found it killed some of my docker container. A way to solve that is to give the box more swap space.
I set it to 4G due to the amount of space/memory I had on my box. Yours may differ.

Create Docker Compose files for HTTPS_PORTAL and Wordpress containers

I have two Docker Compose files to create and run my containers. One is for HTTPS_PORTAL and the other is for MariaDB and Wordpress sites.
Unfortunately, the compose files need to use V1 syntax, due to underlying containers using that old syntax.

HTTPS_PORTAL listens for and will generate LetsEncrypt SSL certs on any containers created that have a VIRTUAL_HOST environment variable set.